.header{
  margin: 28px auto 0;
  display: flex;
  flex-direction: row;
  align-items: flex-start;
  width: 100%;
  border-bottom: 1px solid rgb(84, 84, 84, .7);
  box-sizing: border-box;
  justify-content: space-between;
}

@media screen and (min-width: 880px) {
  .header{
    margin: 45px auto 0;
  }
}